The problem is likely to be a lost connection. The connection between the mouse and the Unifying USB receiver can be lost due to several reasons, including:

• Low battery
• Moving the Unifying USB receiver from one port to another 
• Moving the Unifying USB receiver to another computer 
• Plugging the Unifying USB receiver into a hub or other unsupported. device such as a KVM switch (your Unifying USB receiver must be plugged directly into your computer) 
• Using your cordless mouse on metal surfaces
• Radio frequency (RF) interference from more powerful wireless devices such as:
  • Wireless speakers
  • Computer power supplies
  • Monitors
  • Cellular telephones
  • Garage door openers

Eliminate any potential problems that may be caused by the above possibilities.

Before connecting your M310:

1. Turn your computer on.

2. Insert fresh batteries in your mouse. For instructions on changing your mouse battery, see Knowledge Base article 360023218774

3. Turn on your mouse. The power indicator on the top of the mouse should be green as shown below:

   

4. If the power indicator is not illuminated, move the power switch on the bottom of the mouse (shown below) to on position so the power indicator turns green.

   

5. Plug the Unifying USB receiver directly and securely into a working USB port on your computer..

Re-connecting your M310:

To re-connect your M310, please choose your operating system from the options below:

• Windows
• Macintosh

Windows:

1. Download the correct version of Mouse and Keyboard software (SetPoint) from the M310 Downloads page.

2. Press the Windows key and arrow up to Run.

3. Type C:\Program Files\Logitech\SetPointP\connect.exe.

4. Press Enter.

5. Follow the instructions displayed in the following window:

   

6. Your mouse should re-connect within thirty seconds. If not, the utility will ask you to repeat the process.

7. If re-connection succeeds, you will see the following window:.

   

8. Click Done.

Macintosh:

To re-connect your M310 to a Macintosh computer, do the following:

1. Open a new Finder window (Command + N)

2. Use arrows to go to Applications > Utilities > LCC Connection Utility.

3. Highlight the LCC Connection Utility and press Command + O

4. Follow the instructions displayed in the following window:

   

5. Your mouse should re-connect within thirty seconds. If not, the utility will ask you to repeat the process.

6. If re-connection succeeds, you will see the following windows:

   

Additional Information:

• If the above solutions do not work, please restart your computer and try the reconnections process again.
• " If you are still having problems, consult Knowledge Base article 17892 for instructions on contacting Logitech technical support